Fuel oil compositions



United States Patent 3,110,577 FUEL OH. COMPGSITIONS Jerome E. Brown,Detroit, Mich, and Hymin Shapiro, East Baton Rouge, and Earl G. De Witt,Baton Rouge, La., assign-ors to Ethyl (Importation, New York, N.Y., acorpoi 'ation of Virginia No Drawing. Filed Apr. 6, 1959, Ser. No.804,141 3 Claims. (Cl. 494-68) The present invention relates to improvedhydrocarbon fuel compositions and more particularly to liquid andsemi-solid hydrocarbon fuels for use in heat and light producingapparatus.

Hydrocarbon fuels heavier than gasoline derived from petroleum areutilized in various apparatus such as kerosene lamps, jet type burners,domestic and industrial heating apparatus and the like. They firequentlytend to form excessive soot when the burning rate is increased above acertain point which is dependent upon the rate of air flow supplied tothe combustion zone, the design of the apparatus and the nature of thespecific fuel employed. Thus for any particular combination of variablesthere is a limit in burning rate beyond which it is impractical tooperate in any given system due to the fact that the soot formeddeposits on portions of the apparatus and the fact that the. fuelcarbonizes instead of completely oxidizing which indicates that the heator light producing value is not utilized with maximum efficiency.

' 'It is therefore an object of this invention to provide liquid andsemi-solid hydrocarbon fuels heavier than gasolines which are capable ofhigher burning rates with improved efiiciency. A more specific object ofthis invention is the provision of a liquid hydrocarbon fuel which burnswith high effic-iency and a minimum of soot formation. Still furtherobjects will be apparent from the ensuing description.

The above and other objects of this invention are accomplished byproviding as new compositions liquid and semi-solid hydrocarbonpetroleum distillate and residual fuels heavier than gasoline containinga cyclomatic compound having the general formula MA B wherein M is ametal, namely, nickel; A is a cyclomatic radical, thatis, acyclopentadienyl radical and B is an elec tron donating group such thata +5x+py=S, wherein S is the atomic number of an inert gas of the fourthperiod; namely, krypton; x is a small whole integer, namely, 1; y is asmall whole integer, namely, 1; n is a perlpd of the periodic table,namely, the fourth period; p is the number of electrons donated by theelectron dohating group, namely, 3 and a is the atomic number of themetal, namely, 28/ The amount of such compounds present in thecompositions is regulated such that it is equivalent to from 0.001 toabout 1 weight percent of nickel.

In other words, the new compositions of this invention comprise a liquidor semi-solid hydrocarbon distillate or residual fuel heavier thangasoline and derived from petroleum containing from about 0.001 to about1 weight percent of nickel as a cyclopentadienyl nickel nitrosylcompound wherein the cyclopentadienyl radical preferably contains 5 to13 carbon atoms. As will be seen below, such compositions give rise to agreat reduction in soot formation with an increase in burningefficiency.

3,110,577 Patented Nov. 12, lfifiii ice For most applications thebeneficial results of the practice of this invention are realized whenfrom 0.002 to about 0.3 weight percent nickel is present in the fuel asa cyclopentadienyl nickel nitrosyl compound. This range of metalconcentration is preferred because it may be easily obtained with aminimum of blending control operations, and gives highly satisfactoryresults.

Reference to the generic [formula described hereinabove indicates thatthere are three primary constituents in the additive compounds of thepresent invention. They are the metallic constitutent nickel designatedas M, the cyclomatic or cyc'lopentadienyl radical designated as A and anelectron donating group, namely, the nitrosyl group, NO, designated asB.

The constituent designated by the symbol A in the formula presentedihereinbefore comprises a cyclomatic radical, that is, acyclopentadienyl-type hydrocarbon radical which is a radical containingthe cyclopentadienyl moiety. In general such cyclomatic hydrocarbongroups can be represented by the formulae Where the Rs are selected fromthe group consisting of hydrogen and univalent organic hydrocarbonradicals.

A preferred class of cyolomatic radicals suitable in the practice ofthis invention are those which contain from 5 to about 13 carbon atoms.These are exemplified by cyclopentadienyl, indenyl,methylcyclopentadienyl, propylcyclopentadienyl, diethylcyolopentadienyl,phenylcyclopentadienyl, tert-butylcyclopentad-ienyl,p-ethylphenylcyclopentadienyl, 4- tert-butyl indenyl and the like. Thecompounds from which these are derived are preferred as they are themore readily available cyclomatic compounds and the metallic cyclomaticcoordination compounds obtainable from them have the more desirablecharacteristics of volatility and solubility which are prerequisites ofsuperior hydrocarbon additives. Moreover, they give the most outstandingresults.

The third primary constituent of the new compositions of matter of thepresent invention is desingated as an electron donating group, namely,the nitrosyl group.

Thus, representative compounds of the present invention includecyclopentadienyl nickel nitrosyl, methylcyclopentadienyl nickelnitrosyl, ethylcyclopentadienyl nickel nitrosyl, propylcyclopentadienylnickel nitrosyl, indenyl nickel nitrosyl, methyl indenyl nickelnitrosyl, fiuorenyl nickel nitrosyl, dimethylcyclopentadienyl nickelnitrosyl, lnethylpropylcyolopentadienyl nickel nitrosyl,phenylcyclopentadienyl nickel nitrosyl, and the like.

Still another preferred class of compounds falling within the scope ofthe instant invention are compounds having the formula MA B as definedabove, which are liquids at ordinary temperatures. When compounds of theabove formula, which are liquids, are employed as additives, they havethe important advantages of being readily handled and easily blendedwith liquid hydrocarbons. Outstanding examples of this class of compoundare cyclopentadienyl nickel nitrosyl and methylcyclopentadienyl nickelnitrosyl.

One method for preparing the additives of this invention comprises firstforming a dicyclopentadienyl nickel compound by introducing into acompound of nickel a cyclornatic group or groups and then reacting thisintermediate with nitric oxide, NO. For example, by reacting cyclomaticGrignard reagent such as cyolopentadienyl magnesium bromide, with anickel compound such as EXAMPLE I Under a nitrogen atmosphere, 1.82moles of sodium cyclopentadiene, dissolved in te-trahydrofuran, werereacted with 0.91 mole of anhydrous nickel chloride. The reactionmixture was stirred at room temperature for 18 hours, then heated toreflux for four hours. Most of the tetrahydrofuran was removed bydistillation, the remainder by heating in a steam bath with stirringunder reduced pressure. The residue was sublimed under full vacuum. Overa 36 hour period, 56.0 parts of dicyclopentadienyl nickel were collectedrepresenting a 34.2 percent conversion based on the nickel chloride.

Under a nitrogen atmosphere, 0.29 mole of the dicyclopentadienyl nickelwas dissolved in 500 ml. of petroleum ether boiling in the range of385-50" C. Nitric oxide was bubbled into the dicyclopentadienyl nickelsolution for 1.5 hours. After stirring for one hour, brown-green solidssettled out, leavin a dark red solution which was filtered. The redfiltrate was distilled in a helix-packed column at atmospheric pressureto remove most of the petroleum ether. The remainder was removed underslightly reduced pressure. Fractionation yielded 30 parts ofcyclopentadienyl nickel nitrosyl representing 55 .8 percent conversionbased on the dicyclopentadienyl nickel.

This stable, volatile, gasoline-soluble product is a deep red liquidboiling at 56.5 C./22 mm.

Analysis-Cale. for C H NiNO: Ni, 38.2. Found: Ni, 37.6.

This product along with the other additives is readily soluble inhydrocarbons and most organic solvents including hexane hydrocarbonfuels such as kerosene and diesel fuels, lubricating oils, alcohols,ether, acetone, ethylene glycol, etc.

In the above method of preparation, good results are also obtained inthe manufacture of other compounds of this invention such as indenylnickel nitrosyl, ethylcyclopentadienyl nickel nitrosyl,methylcyclopentadienyl nickel nitrosyl, and the like.

When compounds of the type described above are blended with liquidhydrocarbon distillate fuels to contain from about 0.001 to about 1Weight percent of nickel spectacular results are obtained in thealleviation of soot formation with increase of burning efiiciency.

The base fuels employed in the compositions of this invention aregenerally liquid or semi-solid hydrocarbon compositions derived bydistillation from crude petroleum and include those distillationfractions suitable for use in various burning functions which producelight and/ or heat in a system other than a spark ignition internalcombustion engine as well as the residue fractions from suchdistillations. Thus the distillate fuels generally have initialevaporation temperatures of about 105 F. and final boiling points offrom about 373 F. to about 700 F.

- These fuels have been designated in the art by various terms which areordinarily indicative of their boiling range and other physicalproperties and the use to which the fuel is to be put. However, for anygiven fuel designation thereare ordinarily a variety of somewhat variedspecifications which are applicable. The common names applied to theliquid hydrocarbon fuels employed in this invention include lamp oil,heating oil, kerosene, light petroleum distillate, stove oil, gas oil,household heating fuels, light industrial fuels, heavy industrial oils,stove and lamp naphtha, Number 2 heater fuel or furnace oil, dieselfuels (which may alternatively be employed in heating functions), andthe like. In addition, other designations well known to those skilled inthe art have been employed to characterize the fuels employed in thecompositions of this invention. In general however, it may be statedthat these fuels differ from gasoline not only in the use to which theyare put but in their physical properties. Gasoline, for example, is aspecific cut or blend of petroleum hydrocarbons which has a maximuminitial boiling point up to about F. and a final boiling point never inexcess of about 440 F. In addition, gasoline ordinarily has a flashpoint below 32 F. whereas the fuels employed in the compositions of thisinvention ordinarily will not flash below about 100 F. Furthermore, thegreat majority of fuel compositions employed in this invention haveinitial boiling points in excess of F.

The residual hydrocarbon fuels of this invention are in general highboiling liquid or semi-solid products which comprise the residue fromprimary distillation of crude oil or petroluem. Their main use is infuels for industry boilers. In general, they have flash points ofIOU-200 F., maxim-urn pour points of 15 F. and viscosities rangingbetween 70 and 500 SUS at 100 F. Such residual fuels include the wellknown bunker fuels such as No. 6 fuel oil which consists essentiallyentirely of residual material and No. 5 fuel oil which is made up ofcracker or straight run residual fuel cut back with varying amounts ofdistillate fuel oils of the type described above.

The efficiency of the present compositions can be demonstrated asfollows: A wick-type burner lamp, of the type ordinarily used fordetermination of sulfur in gasoline burns the fuel and produces soot.The burner must be carefully controlled to produce reproducible amountsof soot. Control is accomplished by centrally positioning the burner ina short, cylindrical vertical glass mantle. The burner-mantle assembly,in turn, is centrally positioned Within a longer, cylindrical verticalglass chimney. A base for the entire assembly contains grooves for theprecise location of all parts, and also provides ports to admit air intothe burner and chimney. Soot is collected on a steel plate suspendedhorizontally above the flame at the top of the chimney. This platepartially covers the top of the chimney, but leaves a small opening forexit of combustion gases.

In operation of the burner, the wick of the lamp is carefully trimmedsquare with a constant height of 0.5 cm. A constant weight of fuel,either with or Without an additive of this invention, is added to thelamp. The lamp is then allowed to stand without burning for about 2hours in order to assure uniform adsorption of the fuel by the wick.Then the burner, mantle, and chimney are positioned on the base and thewick lighted. After 30 seconds, the steel collector is put into positionon the chimney top and soot collected for 8 minutes. During this periodfrom about 1.0 to 1.2 grams of fuel is burned. The collector plate thenis carefully removed al id the flame extinguished. The soot is scrapedfrom the plate and weighed. The Weight of fuel burned by the iamp isdetermined. by weighing the lamp before and after test. To eliminate theeffect of minor variations in amounts of fuel consumed during varioustests, the results are expressed as a soot factor, calculated asfollows:

Soot collected, milligrams F Fuel burned, grams Soot factor Additive 8Minute Tests Soot factor None 64.8 Do 60.2 Do 60.9 Do 60.7 Do 61.8 Do63.5 Do 61.2 D 61.9 Average 61.9

.15 -g./gal. Ni as cyclopentadienyl Ni nitrosyl 35 .20 g./ gal. Ni ascyclopentadienyl Ni nitrosyl 29 .47 =g./ gal. Ni as Cyclopentadienyl Ninitrosyl 9.2 .94 g./ gal. Ni as Cyclopentadienyl Ni nitrosyl 5.0

Similar results are obtained with other amounts of this additive withinthe range of concentration described above. Good results are alsoobtained in other distillate and residual fuels of this invention andwith other additives of this invention.

A further demonstration of the remarkable properties of our additives isprovided by their activity in cutting down carbon formation in dieselfuel. This is shown by the following data: The engine was a standardsingle cylinder ASTM diesel engine operated under CFR Method F--543except that the fuel flow rate was 15 cc. per minute instead of 13 cc.per. minute. To the exhaust system of the engine was attached a bypassline provided with a fiberglass filter for collection of carbonparticles from the exhaust stream. The filter and the lines leading toit were held by external heating at a temperature of 212 F. By means ofa valve in the by-pass line the exhaust from the engine could bedirected through a filter for a specified length of time. After each runthe amount of carbon collected on the filter was determined byconventional analytical methods.

The fuel used was a conventional diesel fuel. In several runs in whichthe exhaust was run through the filter at the rate of approximately 6liters per minute until 50 liters of exhaust gas had been passed throughthe filter, cyclopentadienyl nickel nitrosyl exhibited remarkableeffectiveness in decreasing carbon formation. For example, at aconcentration of cyclopentadienyl nickel nitrosyl equivalent to 0.105gram of nickel per gallon the amount of reduction 'of carbon in theexhaust was 22 percent. This reduction was increased to 90 percent at anickel concentration of 1.68 grams per gallon.

Similar results are obtained with other additives of this invention. Useof these additives permits not only a substantial smoke reduction but asan alternate permitsv the obtaining of more power from the diesel enginefor a given smoke level.

The following examples, in which all parts and percentages are byweight, illustrate various specific em bodiments of the compositions ofthis invention employing fuels described above.

EXAMPLE II To :a typical petroleum derived kerosene (1000 parts) havingan initial evaporation temperature of 325 F. and a final evaporationtemperature of 565 F. is added with agitation 17.9 partscyclopentadienyl nickel nitrosyl. The agitation is continued until ahomogeneous blend containing 0.001 weight percent of nickel is achieved.The resulting fuel composition when employed in kerosene lamps or jetburners is found to have superior combustion characteristics than thefuel which contains no additive.

EXAMPLE III To 10.000 parts of a hydrocarbon fuel designated as No. 1heater oil which has an initial evaporation temperature above 350 F. isadded methylcyclopentadienyl nickel nitrosyl in amount sufficient togive a composition of about 1 percent nickel by weight.

EXAMPLE IV To 1000 parts of fuel suitable for use in jet burners havinga 10 percent evaporation point of 220 F., a 90 percent evaporationtemperature of 470 R, an end point of 550 F. and an API gravity of 45 isadded a sufiioient quantity of octyl cyclopentadienyl nickel nitrosyl togive a fuel composition containing 0.002 percent by weight of nickel.This fuel is found to have improved combustion characteristics over thecorresponding fuel without the octyl cyclopentadienyl nickel nitrosyl inthat it burns with a cleaner flame at a higher fuel consumption rate andleaves a minimum of deposits on the interior surface of the apparatus inwhich it is used.

EXAMPLE V To 1000 parts of a furnace oil designated as No. 2 heater oilwhich has an initial evaporation temperature in excess of 380 F. isadded with agitation sufficient indenyl nickel nitrosyl to give acomposition containing 0.01 weight percent nickel.

EXAMPLE VI An improved kerosene blend according to this invention isprepared by adding to 1000 parts of a kerosene having a 10 percentevaporation point of 380 F. and a 90 percent evaporation point of 480F., sufficient ethylcyclopentadienyl nickel nitr-osyl to give acomposition containing 0.3 weight percent nickel.

EXAMPLE VII EXAMPLE VIII To a. fuel suitable for use in jet burnershaving a 10 percent evaporation point of 160 F.-and an end point of 600F. is added cyclopentadienyl nickel nitrosyll in amount sufficient toproduce a final composition containing 0.07 percent nickel which iseminently suited for use as a fuel in jet engines.

EXAMPLE IX Ethyl methylcyclopentadienyl nickel nitrosyl, in amountsuificient to give a composition containing 1.5 weight percent nickel isadded to a fuel suitable for use as a heater or diesel fuel. This fuelhas an initial evaporation temperature of 350 F. and an end point of'580F. When employed either in heating or diesel applications it is found tobe a cleaner burning fuel than the base fuel without ethylmethylcyclopentadienyl nickel nitrosyl. EXAMPLE X Cyclopentadienylnickel n-itrosyl is added to a residual fuel oil having a flash point of160 F., a pour point of 10 F. and a viscosity of 300 SUS F.) in amountsuch that the nickel concentration is 0.001 weight percent.

EXAMPLE XI Methylcyclopentadienyl nickel nitrosyl is added to a lightdiesel fuel consisting of straight r-un gas oil out from paraffiniccrude in amount such that the concentration of nickel is 0.3 weightpercent.

In many applications petroleum distillate and residual fuels heavierthan gasoline are employed in conjunction with other additives besidethe cyclopentadienyl nickel nitrosyl compounds as employed in thisinvention for improving the burning efficiency of the fuel. These otheraliases 6' additives usually comprise antioxidants, dyes, stabilizers,dispersants, corrosion inhibitors, cetane improvers, sludge inhibitors,and the like. It is therefore within the purview of this invention toemploy hydrocarbon distillate and residual fuels heavier than gasolinecontaining a cyclopentadienyl nickel nitrosyl compound in conjunctionwith such additives. Typical of the antioxidant materials employed arealkylated phenols such as 2,6-di-tcrt-butyl phenol, 4,4'-rnethylenebis-2,6-di-tert-butyl phenol, 4- amino-2,6-di-tert-butyl phenol, and2,6-di-tert-butyl-4- methyl phenol and amines such as N,N-di-sec-butylpphenylenediamine and p-n-butylarninophenol. A typical sludge inhibitoris a copolymer of lauryl methacrylate and diethylarninoethylmethacrylate, while various amines and sulfonates are oftenemployed as dispersants. Typical cetane improvers are alkyl nitrates,such as arnyl nitrate and nitrates of polyhydric alcohols andether-alcohols. I

In addition various phosphorus and boron compounds are frequentlyemployed to impart improved stability to the fuels.

This application is a continuation-in-part of application Ser. No.770,290, filed October 29, 1958, now US. Patent 3,006,742, which is acontinuation-in-part of application Ser. No. 698,905, filed November 26,1957, which in turn is a continuation-in-part of application Ser. No.325,224, filed December 10, 1952, now US. Patent 2,818,416.

Having fully described the compositions of the present invention, modesfor their employment and benefits derived therefrom, it is not intendedto be limited except within the spirit and scope of the appended claims.

We claim:

1. A liquid hydrocarbon distillate fuel heavier than gasoline adaptedfor use as an agent to produce light and heat when burned in a light orheat generating apparatus containing from 0.002 to 0.3 weight percent ofnickel as a cyclopentadienyl nickel nitrosyl compound wherein thecyclopentadienyl group is a cyclopentadienyl hydrocarhon group whichcontains from 5 to about 13 carbon atoms.

2. A liquid hydrocarbon distillate fuel heavier than gas adapted for useas an agent to produce light and heat when burned in a light or heatgenerating apparatus containing from 0.001 to 1 weight percent of nickelas a cyclopentadienyl nickel nitrosyl compound wherein thecyclopentadienyl group is a cyclopentadienyl hydrocarhon group whichcontains from 5 to about 13 carbon atoms.

3. The composition of claim 2 wherein said compound is cyclopentadienylnickel nitrosyl.

References Cited in the file of this patent UNITED STATES PATENTS2,560,542 Bartleson et a1 July 17, 1951 2,591,503 Bottoms Apr. 1, 19522,818,416 Brown et al Dec. 31, 1957 FOREIGN PATENTS 1,140,411 FranceMar. 4, 1957 555,282 Canada Apr. 1, 1958

2. A LIQUID HYDROCARBON DISTILLATE FUEL HEAVIER THAN GASOLINE ADAPTEDFOR USE AS AN AGENT TO PRODUCE LIGHT AND HEAT WHEN BURNED IN A LIGHT ORHEAT GENERATING APPARATUS CONTAINING FROM 0.001 TO 1 WEIGHT PERCENT OFNICKEL AS A CYCLOPENTADIENYL NICKEL NITROSYL COMPOUND WHEREIN THECYCLOPENTADIENYL GROUP IS A CYCLOPENTADIENYL HYDROCARBON GROUP WHICHCONTAINS FROM 5 TO ABOUT 13 CARBON ATOMS.